Before an investigation, you will want to create a case history.  This will require you to compile many different kinds of evidence, including eyewitness accounts from people who have seen the ghost or interacted with it, scientific measurements, and, if possible, audio or video recordings of the ghost.

The first step is to build a good history of the location, the land, the building, and the people who live there.

Ø      Witness statements.  Gather as many witness statements as possible.  Try to talk to anyone who’s experienced the haunting.  This includes the people who live in the house, former residents who’ve moved away, friends and guests who stayed at that location, workers who’ve done work inside or outside, and any other ghost hunters who have already investigated the place.

Ø      History of the location.   Find out when the house or location was established or built, if it’s been changed or altered significantly, and its history.  Was it always a house?  Was it once a nursing home, or a bed-and-breakfast?  More importantly, has anyone died at the residence or location, particularly any traumatic or violent deaths, even if that death didn’t occur inside the house?

Ø      History of the land.  Find out, if you can, about the land where the building or location was built/made.  Was it once used for another purpose?  Was the land used as a graveyard or execution site?  Was it a campground, playground or hiking area?

Ø      Alternative explanations.  This will require some detective work.  Any good ghost hunter will look for an ordinary explanation for the occurrences before moving on to supernatural possibilities.  If people hear scratching at the window, is there a tree outside with branches hitting the winfdow?  Or is here a resident cat who enjoys perching on the sill?  If there are spooky footsteps heard in an apartment, is there a staricase outside or heavy-footed people who live above?  Is the house old, with wooden floors?  Remember, a good ghost hunter is a good detective as well!